WO2010127806A1 - Procédé d'utilisation conjointe de points d'accès sans fil à un réseau de communication - Google Patents

Procédé d'utilisation conjointe de points d'accès sans fil à un réseau de communication Download PDF

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Publication number
WO2010127806A1
WO2010127806A1 PCT/EP2010/002634 EP2010002634W WO2010127806A1 WO 2010127806 A1 WO2010127806 A1 WO 2010127806A1 EP 2010002634 W EP2010002634 W EP 2010002634W WO 2010127806 A1 WO2010127806 A1 WO 2010127806A1
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WO
WIPO (PCT)
Prior art keywords
network node
communication terminal
network
communication
data
Prior art date
Application number
PCT/EP2010/002634
Other languages
German (de)
English (en)
Inventor
Wolfgang Kiess
Björn Scheuermann
Till Elsner
Martin Mauve
Original Assignee
Heinrich-Heine-Universität Düsseldorf
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Heinrich-Heine-Universität Düsseldorf filed Critical Heinrich-Heine-Universität Düsseldorf
Publication of WO2010127806A1 publication Critical patent/WO2010127806A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/02—Network architectures or network communication protocols for network security for separating internal from external traffic, e.g. firewalls
    • H04L63/0272—Virtual private networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W12/00—Security arrangements; Authentication; Protecting privacy or anonymity
    • H04W12/08—Access security
    • H04W12/084—Access security using delegated authorisation, e.g. open authorisation [OAuth] protocol
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00—Network architectures or network communication protocols for network security
    • H04L63/06—Network architectures or network communication protocols for network security for supporting key management in a packet data network
    • H04L63/061—Network architectures or network communication protocols for network security for supporting key management in a packet data network for key exchange, e.g. in peer-to-peer networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/10—Small scale networks; Flat hierarchical networks
    • H04W84/12—WLAN [Wireless Local Area Networks]

Definitions

  • the present invention relates to a method for establishing a communication connection between a mobile communication terminal and a first network node assigned thereto via at least one second network node of a communication network.
  • the field of application of the present invention is the construction of a completely decentralized network for the shared use of public or private, in particular wireless, Internet connections by mobile Internet users without a central authority for authenticating the mobile Internet user or his communication terminal.
  • shared use is also referred to as "access point sharing”.
  • wireless public access points exist, which in English terminology are called “wireless LAN (WLAN) access points”.
  • WLAN wireless LAN
  • Such access points also called “hotspots”
  • the Internet users can wirelessly connect via their communication terminal to gain access to the network.
  • a communication terminal can be used any mobile device, such as a notebook, a PDA (Personal Digital Assistant) or a mobile phone. If the communication network is the Internet, the communication terminal is designed to be Internet capable.
  • These central authentication instances are operated by a service provider to which the mobile user is a customer.
  • the authentication entity thus knows the user and his trustworthiness and assures the network node over which the internet user desires access to the internet, its authorization and trustworthiness. This means that the network access node must have full trust in granting access to the authentication authority's network. This enforced trust, especially in connection with liability risks of the operator of the network node, keeps many users from participating in an access point sharing with a decentralized network structure. This will be explained in more detail below.
  • a network is created by the fact that the mobile guests make their domestic Wi-Fi access available to other guests.
  • the creation and use of distributed networks creates legal problems, as the network node through which an Internet user accesses the Internet is legally responsible for ensuring that its users do not exceed legal limits. This is the case, for example, when the internet user downloads copyrighted works its communication terminal over the network node freely available or offers media with child pornographic content over the Internet via this network node. If this happens over the used network node, there is an abusive use of this access point. This is particularly problematic if the identity of the actual polluter can not be traced in a completely reliable manner and subsequently verified by the operator of the access point.
  • protection of the network node used can be ensured by the authentication of the Internet user, the protection depends on the reliability of the authentication entity.
  • the operation of a corresponding authentication authority is relatively complicated, since it requires a not inconsiderable network infrastructure and also makes at least one identification of the Internet user via a usually carried out by postal identification process necessary. If the authentication authority does not perform such an identification of the internet user, the network node can not trust that the internet user is actually the one he pretends to be in a network access request.
  • the described protection mechanism using a central authentication entity is therefore subject to a certain security risk for the network node.
  • a network node associated with a mobile communication terminal is used as a trusted relay station to go on the Internet.
  • the communication terminal initially accesses a first network node, then establishes a secure tunnel to a second network node and accesses the Internet via this second network node, whereby this access is granted by the communication terminal of the relay station issuing a certificate issued by a central authentication entity transmitted, evidenced by which the communication terminal is authorized to access the Internet.
  • the secured tunnel between the communication terminal and the second network node acting as a relay station ensures that the data packets transmitted by the communication terminal are regarded as coming from the second network node from the perspective of the communication network.
  • the network node providing the network access thus only has to trust the issuer of the certificate and then transfers any legal liability risk to the second network node.
  • a central instance is also necessary in this method, which assures the second network node by means of a certificate that the internet user may access the communication network and for this purpose may communicate with a specific first network node.
  • a certificate may be stolen, forged or even falsified, so that an Internet user acting in the event of damage could still move the second network node to forward its data to the communication network or to a network node selected by the Internet user.
  • the second network node thus still relies on trusting a central entity and the accuracy of the issued certificates, which still carries a security risk for him.
  • a method for establishing a communication connection between a mobile communication terminal and a first network node assigned to it via at least one second network node of a communication network, in which the communication terminal transmits a connection request to the second network node to the first network node and the second network node then requests the first network node, send him data for the authorization of the communication terminal, wherein the first network node then transmits data for authorization to the second network node and after successful authorization by the second network node of the communication terminal via the second network node connects to the first network node and a data transfer between the communication terminal and the first network node via the second network node.
  • This method makes it possible to manage without a central authentication entity or certificate issuing authority, since the second network node assigned to the communication terminal provides the data necessary for the authorization of the communication terminal. The authorization itself then takes place through the second network node.
  • a communication network with many communication terminals and according to these associated network nodes thus creates a decentralized network with a decentralized authorization of the communication terminals and the corresponding users.
  • This has the advantage that the network node between the communication terminal and the first network node no longer has to trust a third party, since the structure of the communication connection is based exclusively on a trust relationship between the communication terminal and the first network node associated therewith. The existence of this trust relationship can be checked by the second network node without the help of a central instance.
  • the mobile communication terminal may be, for example, a notebook, a PDA (Personal Digital Assistant), a mobile phone or any other, in particular internet-capable communication terminal.
  • the first network node may be, for example, a computer from which the communication terminal wishes to retrieve data or to which the communication terminal wishes to transmit data.
  • the first network node may be a private access point to the communication network, for example a router that belongs to the user of the communication terminal and that is already assigned to the communication terminal due to this relationship.
  • the access point of the first network node can be implemented wirelessly, so that the first network node grants a so-called WLAN access to the communication network, i. represents a wireless access point.
  • the network node designed as the first network node can be used to grant the communication terminal access to the communication network, only after successful authorization of the communication terminal this via the second network node, the connection to the first network node and from this in turn is granted to the communication network.
  • the first network node is thus used as a relay station over which the data communication between the communication terminal and the communication network is performed.
  • the second network node may also have a network access in this embodiment, which may be preferably carried out wirelessly.
  • the second network node may be a public or a private access point, that is to say another internet user or another communication terminal, in the form of a router or a computer, via which access to the communication network is possible.
  • connection between the communication terminal and the first network node can be made via a VPN (Virtual Private Network) tunnel.
  • VPN Virtual Private Network
  • the data transmitted by the communication terminal to the second network node may have been digitally authenticated by the communication terminal.
  • cryptographic methods are used in which added to a group of arbitrary data as a cryptographic checksum additional data are added, which are uniquely associated with the data.
  • a key is used, which is known to the communication terminal and the second network node. The second network node, after checking the cryptographic checksum, can be sure that the data transmitted to it is from the correct sender, i. the previously asked for connection to the first access node communication terminal.
  • the method according to the invention can be applied to any decentralized network, ie for example to a decentralized network with a plurality of network nodes with access points, in which the users each provide these private access points to other users, ie provides access point sharing ,
  • the second network node can be assigned to a second mobile communication terminal and establish a connection to the second network node at least via the first network node, the second communication terminal transmitting a connection request to the first network node to the first network node and the first Network node then requests the second network node to transmit data for the authorization of the second communication terminal, the second network node then transmits data for authorization to the first network node and after successful authorization by the first network node from the communication terminal via the first network node connects to the second network node and from this in turn can be made to the communication network.
  • the assignment of a network node to a communication terminal according to the invention can take place in that they both a first cryptographic key is known.
  • This cryptographic key can be selected manually by an Internet user and communicated manually to his communication terminal and private network node.
  • a key can be a password or a random sequence of numbers and letters. Due to the fact that both the communication terminal and the network node associated with it are in possession of the same key, there is a trust relationship between them which can be used for authorization of the communication terminal.
  • the steps used to authorize the communication terminal may, for example, be as follows:
  • the network node requested to transmit the authorization data selects a second cryptographic key, which it then encrypts using the first cryptographic key.
  • the vote The second cryptographic key can be made by selection from a set of existing keys or by generating a new key.
  • the network node sends both the unencrypted second cryptographic key and its encrypted form to the requesting network node, which retains the second cryptographic key and only forwards the encrypted form of this second cryptographic key to the communication terminal.
  • the communication terminal can decrypt the encrypted form of the second cryptographic key using the first cryptographic key. This is possible because the communication terminal is in possession of the first cryptographic key that has been used to encrypt the second cryptographic key.
  • the second cryptographic key is now known to both the communication terminal and the requesting network node.
  • the communication terminal can now prove to the requesting network node that it possesses the second key. This proof proves that the communication terminal has a trust relationship with the requested network node.
  • the proof can be carried out, for example, by a cryptographic checksum, which generates the communication terminal with the aid of the second cryptographic key and appends it at least once to the network node to be transmitted data, the network node can check the checksum by means of the known second cryptographic key. If the checksum is correct, the network node knows that the transmitted data originates from the communication terminal that has a trust relationship with the network node requested for authentication.
  • a cryptographic checksum which generates the communication terminal with the aid of the second cryptographic key and appends it at least once to the network node to be transmitted data
  • the invention relates to a communication network comprising at least one mobile communication terminal, a first network node assigned thereto and at least one second network node, wherein a communication connection to the first network node can be set up by the communication terminal at least via the second network node, and the communication terminal, the first and the second Network nodes are set up to carry out the method described above.
  • a second communication terminal can be provided, which in turn is assigned to the second network node and desires a communication connection via the first network node, the involved components also being configured to perform the above-described methods.
  • Figure 1 Schematic representation of the data transmission path after establishing the communication connection
  • Figure 2 schematic representation of the procedure for establishing the communication connection
  • FIG. 1 shows a communication network comprising at least one mobile communication terminal G, a first network node R assigned to it and at least one second network node H, wherein from the communication terminal G via the second network node H a communication connection to the first network node R and from this to any computer of the Communication network is constructed, which represents the Internet according to Figure 1.
  • the communication terminal G is designed as a notebook and accesses via a wireless communication connection to the configured as a network access point second network node H.
  • the first Network node R also includes a network access point through which the communication terminal G gains access to the Internet.
  • the first network node R is assigned to the communication terminal G in such a way that both the communication terminal G and the first network node belong to the same Internet user. Furthermore, the assignment is characterized in that both of them know one and the same cryptographic key s.
  • the second network node H serves as a relay station, since it forwards the data originating from the communication terminal G to the first network node, which can be regarded as a remote-controlled station.
  • the first network node in turn serves as a relay station for the data of the communication terminal G 1 by forwarding them to the Internet and incoming replies to the communication device.
  • NAT network address translation
  • the first network node replaces the sender address in the case of data forwarded by the communication device in the direction of the Internet by an address assigned to it itself, and replaces the destination address by an address assigned to the communication terminal G in response data received thereon.
  • the communication terminal G and the first network node R there is a secure connection in the form of a tunnel. An access of the communication terminal G to the Internet is consequently only possible via the first network node R.
  • FIG. 2 shows a sequence according to the invention of the authentication method for setting up the communication connection. It is shown that both the communication terminal G and the first network node R, the same key s is known.
  • the communication terminal G first provides the second network node H with a connection request to the first network node R.
  • the second network node H requests the first network node R to provide the necessary data for the authorization, ie the authorization of the communication terminal G 1 first network node to establish a connection to check.
  • the first network node R selects a second cryptographic key t and encrypts it by means of the first cryptographic key s known to it to a ciphertext s (t).
  • Both the second cryptographic key t and the associated ciphertext s (t) are then transmitted by the first network node R to the second network node H, which retains the second cryptographic key t and forwards the ciphertext s (t) to the mobile communication terminal G.
  • the second cryptographic key t is used to authenticate this data p. This is done by forming a checksum HMAC (Keyed Hash Message Authentication Code), which is appended to the data p. If the data p consists of several data packets to be arranged in a specific order, a sequence number sn can be formed for the composition of the packets in the correct order at the receiving location, which sequence is also appended to the data p or the data sequence. The data formed from the data packets and the sequence number are then jointly authenticated, ie a checksum HMAC formed using the second cryptographic key t.
  • HMAC Keyed Hash Message Authentication Code
  • the second network node H Since the second network node H is in possession of the second key t, it can check the cryptographic checksum HMAC and, in case of a match, be sure that the data originates from the sender who maintains a trust relationship with the first network node. The second network node H can thus transfer the data p to the first network node R without any security concerns.
  • the communication terminal may also be referred to as guest G, the first network node as remote station G and the second network node as host G.
  • guest G After the guest G has made contact with the host G - for example, by logging into a provided for this wireless network and there received a local address - asks the guest G at the host G to connect to his remote station G allowed to.
  • host G there is no central instance by means of which host G could verify the identity of the guest G and assign it to a specific remote station.
  • the mechanism described in this invention allows the host G to check the membership of the guest G to the remote station G and thus to ensure the authorization of the guest G to communicate with the remote station G designated by this. For this purpose, no centrally authenticated identity characteristics of the guest G are required. In particular, it is even possible to verify the affiliation of the guest G to the remote station G and thus determine the authorization for data transmission without the host G being aware of the identity of the guest G or the remote station G. Also, for verification purposes, no direct communication between guest G and remote station G must be allowed.
  • the sequence of an authorization according to the invention is the following, it is shown in FIG. 2:
  • the host G receives a connection request from a guest G, he contacts the remote station G named in this connection request and requests the provision of a temporary key t for the authorization of the guest G.
  • the guest and the remote station G already share a secret key s.
  • the remote station G selects a key t and encrypts it with the key s. Both the selected key itself t and the encrypted key s (t) are transmitted to the host G.
  • the guest G and the host G now have a shared secret t, which allows the host G the actual authorization check of the guest G.
  • the guest G is not in possession of the key s, he has no possibility to conclude from the key transfer s (t) to the chosen key t.
  • the fact that the guest G is in possession of the key t shows that he also holds the key s then owns and then assists the host G that a trust relationship exists between the guest G and the remote station G, and that the remote station G is ready and willing to receive guest G's data.
  • Authentication of data traffic generated by the guest G and directed to the remote station G by means of the key t exchanged in the course of the mechanism can be effected, for example, by a cryptographic checksum.
  • the guest would use the key t to attach to the transmissions of the data packets p generated by him such a hash (hashed message authentication code, HMAC).
  • HMAC hash
  • a serial number sn would also be included here to prevent possible attacks by repeating previously recorded transmissions.
  • the host G can, if such a message arrives, use the same key t to compute the same checksum and compare it with the one transmitted. A correct checksum then proves that the creator of the message is in possession of the key t is, and thus confirms the host G that the data packet p may be forwarded to the remote station G.
  • symmetric cryptography can be replaced by asymmetric cryptography.
  • each network node which would have knowledge of the respective symmetric key according to the described method steps, at least one of the keys of the corresponding asymmetric key pair.

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Computer Hardware Design (AREA)
  • Computing Systems (AREA)
  • General Engineering & Computer Science (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne un procédé d'établissement d'une liaison de communication entre un terminal de communication mobile (G) et un premier nœud de réseau (R) hiérarchiquement supérieur, via au moins un deuxième nœud de réseau (H) d'un réseau de communication. Pour ce faire, le terminal de communication (G) envoie au deuxième nœud de réseau (H) une demande de liaison avec le premier nœud de réseau (R). Le deuxième nœud de réseau (H) invite alors le premier nœud de réseau (R) à lui fournir des données pour l'autorisation du terminal de communication (G). Le premier nœud de réseau (R) transmet ensuite ces données d'autorisation au deuxième nœud de réseau (H). Après réussite de l'autorisation par le deuxième nœud de réseau (H), une liaison est établie avec le premier nœud de réseau (R) par le terminal de communication (G), via le deuxième nœud de réseau (H), et un transfert de données se produit entre le terminal de communication (G) et le premier nœud de réseau (R), via le deuxième nœud de réseau (H). L'invention concerne en outre un réseau de communication pour la mise en œuvre du procédé.
PCT/EP2010/002634 2009-05-06 2010-04-29 Procédé d'utilisation conjointe de points d'accès sans fil à un réseau de communication WO2010127806A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102009019864.4 2009-05-06
DE102009019864A DE102009019864A1 (de) 2009-05-06 2009-05-06 Verfahren zur Mitbenutzung drahtloser Zugangspunkte zu einem Kommunikationsnetzwerk

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WO2010127806A1 true WO2010127806A1 (fr) 2010-11-11

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WO (1) WO2010127806A1 (fr)

Cited By (1)

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CN117641355A (zh) * 2023-11-27 2024-03-01 中时讯通信建设有限公司 一种网络接入方法、系统、设备、可存储介质及通信方法

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EP1542401A1 (fr) * 2003-12-11 2005-06-15 Swisscom AG Point d'acces pour des reseaux sans fil locals

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WO2001022685A1 (fr) * 1999-09-20 2001-03-29 Telefonaktiebolaget Lm Ericsson (Publ) Procede et systeme d'etablissement de connexions protegees
EP1542401A1 (fr) * 2003-12-11 2005-06-15 Swisscom AG Point d'acces pour des reseaux sans fil locals

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117641355A (zh) * 2023-11-27 2024-03-01 中时讯通信建设有限公司 一种网络接入方法、系统、设备、可存储介质及通信方法

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